4. Execute the rdf2binary tool, it will output dict.desc and dict.index

5. Copy dict.desc and dict.index to /.rockbox/rocks/apps on the player.

The rockbox dictionary format

The input format for rdf2binary is very simple at this moment. It's one line per word, starting with the word, then a tab and then the description. The only thing you should be aware of when creating this files is that they must be in alphabetical order, and all words should be in lowercase.

The binary format

The binary format used for the index is pretty simple, the struct is like this one:

struct {
char word[WORDLEN];
long offset;
};

WORDLEN is a define in the rdf2binary tool, and the plugin.
And the offset is an offset in dict.desc where the description is stored.

The improved binary format

This is still an idea under construction, but the new format would be just 1 file containing:

When searching for a word with hash X, the plugin looks up the offset for X and X+1 in the offset table.
It reads the data between those offsets on looks for the word, we were searching for.
It's just a hash table with chaining.